Vertical axis wind turbine rotor construction

ABSTRACT

A Savonius vertical axis wind turbine (VAWT) rotor is easily and simply constructed while having enhanced functionality. The rotor includes a shaft that is vertical in use, a number (desirably at least four) of vane support hubs each having a number (desirably three) of at least partially curved spokes extending radially outwardly, and a number of vanes corresponding to the number of spokes. The vane support hubs are operatively connected directly to the shaft and spaced vertically from each other along the shaft to provide a plurality of sets of vertically spaced spokes. The vanes, one for each set of spokes, are operatively connected to the spokes to provide surface area for engaging wind and rotating the shaft when in use. Desirably the vane support hubs are operatively connected to the shaft using mechanical fasteners, and the vanes are connected to the spokes using mechanical fasteners. Structural end caps are not necessary, and therefore the rotor is devoid of them. The vane support hubs and spokes are desirably integral and made of metal or fiber reinforced plastic, and the vanes may be made of sheet metal. Further provided is a vane support assembly for a Savonius or open helix VAWT including a vane support hub defining an opening, a number of at least partially curved spokes integral with the vane support hub and extending radially outwardly, and an adaptation part of the hub which allows it to be operatively connected to a shaft extending through the opening. Also provided is a complete Savonius or open helix VAWT.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of co-pending U.S. application Ser. Nos. 10/443,954 and 10/443,961, both filed May 23, 2003. Also, this application claims the priority of U.S. provisional application 60/386,569 filed Jun. 7, 2002.

BACKGROUND AND SUMMARY OF THE INVENTION

Various types of vertical axis wind turbine (VAWT) rotors have been proposed in the past for use with a wide variety of devices, including pumps, propellers, and for generating electricity. The Savonius VAWT has been known since the 1920s, but has not yet been widely implemented commercially. Also, there is a general feeling in the art that it is unsuitable for commercial generation of electricity.

A conventional drawback of the Savonius VAWT is often considered to be its cumbersome construction, which includes two or more structural end caps. Typically, a plurality of vanes (normally two in practice) are mounted between two end caps, or if more than one stage is provided, then one or more intermediate “end” caps are provided. The end caps often provide the major structural support for the vanes, and are connected to a shaft for rotation about a vertical axis [see, for example, Sigrud Savonius' U.S. Pat. No. 1,697,574 and British Patent 244,414].

In U.S. Pat. No. 4,830,570 a version of a Savonius VAWT is provided which in addition to end caps, uses a structural support system for indirectly connecting the vanes (the patentee calls them “blades”) to a central shaft. At spaced locations along the shaft the patentee provides structural members extending radially from a sleeve which surrounds and is rigidly attached to the shaft. At those locations ribs are connected to the vanes and extensions of those ribs are connected to the radial structure members. Also further diagonal structural members connect the ribs to the radial structural members, providing a complex arrangement that appears to be very difficult to construct, and undesirably expensive. While the patentee suggests that for very small rotors a much simpler design would work, how the design would be simpler is not described.

According to the invention, a Savonius VAWT rotor is provided that undoubtedly performs at least as well as the rotor in the '570 patent yet is much, much simpler, eliminating components apparently considered necessary in the '570 patent without elimination of their function. According to the invention, a Savonius VAWT is provided wherein vane support hubs are provided with curved spokes extending radially outwardly therefrom and preferably integral therewith (e.g. formed of the same piece of metal). The hub directly engages and is operatively connected to the shaft. No structural end caps, separate radial structural supports, or diagonal structural supports, as are utilized in the '570 patent arrangement, are necessary, yet the rotor maintains structural integrity and functions well even in high winds. The hubs may also be operatively attached to the shaft by removable fasteners, for quick assembly of the rotor, and to allow disassembly for repair or reconstruction if necessary.

According to one aspect of the invention there is provided a Savonius vertical axis wind turbine rotor comprising: A shaft, substantially vertical in use. A plurality of vane support hubs each having a plurality of at least partially curved spokes extending substantially radially outwardly therefrom. The vane support hubs are operatively connected directly to the shaft and spaced vertically from each other along the shaft to provide a plurality of sets of vertically spaced spokes. And a plurality of vanes, one for each set of spokes, operatively connected to the spokes to provide surface area for engaging wind (which causes the shaft to rotate during use, when mounted in bearings). Providing the construction according to the invention, the rotor is devoid of structural end caps, greatly simplifying the construction, improving appearance, and reducing the weight of the structure significantly (all other things being equal).

In one form of the invention, each vane support hub has exactly three spokes. It has been found that three spokes (and thus three vanes) are desirable for many purposes despite prior art teachings indicating that three vanes are much less desirable. [E. g. see column 9, lines 38+ of the '570 patent, the cancellation of the three vane version from the Savonius British patent, and the 1977 finding in the Sandia Laboratories report “Wind Tunnel Performance Data for Two- and Three-Bucket Savonius Rotors” SAND76-0131 at page 31 that “The maximum power coefficient of the two-bucket configuration is approximately 1.5 times that for the three-bucket configuration”.]

Preferably, the vane support hubs are operatively connected to the shaft using mechanical fasteners, such as removable fasteners. Also, the vanes may be connected to the spokes using mechanical fasteners. The mechanical fasteners may directly connect the vane support hubs to the shaft.

It is desirable that at least four vane support hubs are provided vertically spaced along the shaft, with the spoke sets thereof substantially vertically aligned with each other. The vane support hubs and spokes are preferably integral and made of metal (e.g. aluminum or titanium) or fiber (e.g. carbon fiber) reinforced plastic. The vanes may be made of sheet metal, or high performance sail cloth.

The Savonius VAWT rotor may be provided in combination with at least one bearing assembly mounting the shaft substantially vertically for rotation about a substantially vertical axis, and a propeller, electricity generating device, or pump operatively connected to the shaft to be powered thereby.

According to another aspect of the invention, a vane support assembly for a Savonius or open helix vertical axis wind turbine is provided comprising: A vane support hub defining a substantially central through-extending opening therein. A plurality of at least partially curved spokes integral with the vane support hub and extending substantially radially outwardly therefrom; and an adaptation part of the hub which allows the hub to be operatively connected to a substantially vertical shaft extending through the through-extending opening, for rotation with the shaft. The adaptation may be an opening in a part of the hub, such as a radial opening in the hub which extends to the through-extending central opening and is adapted to receive a mechanical fastener, keying on the hub, or a variety of other structures. As with the rotor, the vane support hub per se may include exactly three integral spokes, and the vane support hub and integral spokes may be made of metal or fiber reinforced plastic.

According to another aspect of the invention there is provided a Savonius or open helix VAWT comprising: At least one bearing. A substantially vertical shaft mounted by the at least one bearing for rotation about a substantially vertical axis. At least four vane support hubs each having a plurality of at least partially curved spokes extending substantially radially outwardly therefrom. The vane support hubs are operatively connected (e.g. directly) to the shaft and spaced vertically from each other along the shaft to provide a plurality of sets of vertically spaced spokes. The turbine is devoid of structural end caps. A plurality of vanes, one for each set of spokes operatively connected to the at least partially curved spokes to provide surface area for engaging wind; and a propeller, electricity generating device, or pump operatively connected to the shaft to be powered thereby. As with the rotor, if desired three spokes are provided for each vane support hub, and the spokes and hub may be integral.

The presently claimed features of the invention, or aspects thereof, are mostly clearly seen in FIGS. 31-37, 45 & 46 of the appended drawings (and are described in the text associated therewith).

It is the primary object of the invention to provide a desirable construction of a VAWT, rotor therefor, and vane support assembly therefor. This and other objects of the invention will become clear from a detailed inspection of the invention, and from the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of an exemplary vertical axis wind turbine multi-hull watercraft that may utilize the invention;

FIG. 2 is a front schematic view of a conventional sixteen foot Hobiecat® catamaran;

FIG. 3 is a view like that of FIG. 2 only showing wind turbine mounting structure modifications;

FIG. 4 is a schematic side assembly view of the mounting structure of FIG. 3 in association with a wind turbine and horizontal propeller drive system according to the invention;

FIG. 5 is a side schematic detail view of the exemplary gear and clutch mechanism of FIG. 4;

FIG. 6 is a top exploded view of the mechanism of FIG. 5;

FIG. 7 is a view partly in cross-section and partly in elevation showing the cooperation between the gear tube and shaft extension of FIG. 4;

FIG. 8 is a schematic side view of an exemplary horizontal propeller drive gear assembly and propeller for driving an exemplary watercraft according to the invention;

FIG. 9 is a schematic front cross-sectional view, taken along shaft 44, of the watercraft of FIG. 1 showing one exemplary form of drive shaft and horizontal propeller mounting structures according to the invention;

FIG. 10 is a side view, partly in cross-section and partly in elevation, of the intermeshing gears of FIGS. 4 & 8 with a front hydrodynamic cover;

FIG. 11 is a view like that of FIG. 4 but showing a modified gear assembly according to the invention;

FIG. 12 is a side schematic view of the gear tube and shaft extension of FIG. 4 only in association with a vertical axis propeller;

FIG. 13 is a view like that of FIG. 4 only showing an exemplary fishtail propulsion system according to the invention instead of a horizontal propeller;

FIG. 14 is a bottom view of the propulsion system of FIG. 13;

FIGS. 15-17 are top plan views of individual components of the propulsion system of FIGS. 13 & 14;

FIGS. 18-20 are top plan view of alternative constructions of the fishtail propulsion system of FIGS. 13-17;

FIG. 21 is a side view of one exemplary manual assist for powering the watercraft of FIG. 1 according to the invention;

FIG. 22 is an end view of the pawl and ratchet assembly of the manual assist of FIG. 21;

FIGS. 23 and 24 are top and partial side views, respectively, of an exemplary modified form of a large curvature-vane Savonius wind turbine;

FIGS. 25 and 26 are views like that of FIGS. 23 and 24, respectively, of a modified form of overlapping vane Savonius wind turbine;

FIG. 27 is a side schematic view of the operator-interactive components of a preferred manual assist according to the present invention;

FIG. 28 is a top, schematic, partial view of the components of FIG. 27 shown connected to the shaft of the vertical axis wind turbine of a watercraft according to the invention;

FIG. 29 is a schematic side view of the components of the manual assist of FIGS. 27 & 28 associated with the wind turbine shaft;

FIG. 30 is a schematic isometric view of a paddlewheel form of drive mechanism for the watercraft according to the invention;

FIG. 31 is a schematic top perspective view of a open helix form of a collapsible vertical axis wind turbine according to the invention;

FIGS. 32-34 are perspective, top, and end views of an exemplary vane support used with the collapsible vertical axis wind turbines of FIGS. 31, 35 & 36;

FIG. 35 is a side view, partly in cross section and partly in elevation, of the operative position of a Savonius form of collapsible vertical axis wind turbine according to the present invention, which uses the vane supports of FIGS. 32-34;

FIG. 36 is a view like that of FIG. 35 only showing the wind turbine in a collapsed position;

FIG. 37 is a schematic top perspective view of a modification of the wind turbine of FIG. 31 having spokes of the lower vane support of shorter length;

FIG. 38 is a side schematic view, partly in cross section, of a watercraft according to the invention showing a flexible drive shaft according to the invention;

FIG. 39 is a top plan view of the watercraft of FIG. 38;

FIG. 40 is a schematic exploded perspective view of one form an exemplary clutch mechanism utilizable with the flexible drive shaft of FIGS. 38 & 39;

FIG. 41 is a front view of an exemplary football shaped hull of a catamaran according to the present invention;

FIG. 42 is a view like that of FIG. 35 of a bottom-supported embodiment of vertically collapsible wind turbine according to the invention, with some components removed for clarity of illustration;

FIG. 43 is a view of the structure of FIG. 42 showing the two bottom vane assemblies in a collapsed condition;

FIG. 44 is a view taken along lines 44-44 of FIG. 42, with some of the lower components removed for clarity of illustration;

FIG. 45 is a view like that of FIG. 42 only showing a linkage embodiment of a collapsible wind turbine according to the invention (and also illustrating a readily detachable vane embodiment); and

FIG. 46 is a schematic perspective view of the main vane support—and associated structures—of the linkage embodiment of FIG. 45, and a partial perspective view of the bottom of an exemplary vane of both the linkage embodiment and readily detachable vane embodiment.

DETAILED DESCRIPTION OF THE DRAWINGS

In the drawings, the following reference numerals have the following general descriptions:

 10 Watercraft  11, 12 Hulls  13, 14 Crossbars  15 Wind turbine  16 Support tube  17 Wind turbine shaft  18 Bearing(s)  19 Bracket(s)  20 Shaft extension  21 Splines  22 Drive gear  23 Clutch assembly  24 Handle support surface  25 Gear tube  26 Internal splines  27 Gear tube collar  28 Collar undersurface  29 Gear surface  30 Driven gear  31 Clutch plate or bar  32 Top surface of 31  33 Pivot pin  34 Support plate  35 Operating lever  36 Front end of 31  37 Width of cutout in 31  38 Stop  39 Spring  40 Bearing or mount  41 Propeller drive assembly  42 Shaft  43 Universal Join  44 Propeller shaft  45 Horizontal propeller  46 Bearing or mount for 44  47 Handle portion of lever 35  48 Strap  49 Leaf Spring  50 Brackets  51 Struts of 50  52 U-shaped portion of 50  53 Leaf Spring  54 Hydrodynamic cover  55 Struts for 54  57 Reverse gear  59 Detent  60 Coil spring  62 Vertical Propeller  63 Gearing  64 Rudders  65 Core of 86  66 Covering of 65/86  67 Supporting ribs for 66  68 Dolphin striker post  69 Dolphin striker rod  70 Propulsion system  71 Drive element (crank arm)  72 Guide element  73 Oscillating element  74 Non-round hole in 71  75 Hole in 71  76 Pivot pin  77 Hole in 73  78 Front end of 73  79 Elongated slot  80 Bracket  81 Pivot pin  82 Middle opening in 73  83 Spring  84, 85 Caps  86 Free end of 73  90 Cam  91 Cam lobes  92 Cam follower  93 Lever  94 Pivot  95 Portion of 93  97 End of lever 101  98 Cam  99 Cam track 100 Cam follower 101 Oscillating lever 102 Pivot pin 103 Free end of 101 104 Disconnect (clutch) 105 Manual assist 106 Ratchet wheel 107 Drive pawl 108 Lever 109 Catch pawl 110 Support structure 111 Coupler 112 Crank arm 113 Pivot 114 Knob/handle 116 Pivot pin 117 Elastic band loop 120 Savonius wind turbine 121 Savonius wind turbine 122 Vanes of 120 123 Vanes of 121 125 Perforated shaft of 120 126 Perforated shaft of 121 127 Perforations of shaft 125 128 Vane 122 end terminations 129 Vane 123 end terminations 130 Passage-defining elements 131 Planar end of 123 132 Shaft 126 flat sides 133 Perforations of shaft 126 134 Preferred manual assist 135 Seat mounting rail(s) 136 Reciprocal seat 137 Hole in rail 138 Hole in seat flange 139 Seat flange 140 Locking pin for holes 137,8 141 Manual assist operator 142 First [arm] drive assembly 143 Second [leg] drive assembly 144 Support arm 145 Pulley 146 First cord 147 Handle 148 First cord drum 149 First drum take-up 150 Pulley 151 Pulley mounting shaft 152 First one-way clutch 154 Second cord 155 Front of seat 136 156 Pulley 157 Pulley 158 Second cord drum 159 Second drum take-up 162 Second one-way clutch 163 Foot plates 164 Foot plate straps 170 Drive gear 171 Face gear 172 First paddlewheel 173 Reversing gear 174 Face gear 175 Second paddlewheel 215 Vertically collapsible wind turbine 215′ Modified vertically collapsible wind turbine (other primed reference numerals are the FIG. 37 modified forms of the original reference numeral structures); 215 A, 215 B, other modifications of collapsible wind turbines 220-222 Vane supports 223-226 Spokes 227 Vane support hub 228 Central vertical bore 229 Pin-receiving horizontal bore 231, 232 Locking pins 233 Holes in shaft 17 for pins 234 Pin projections 235 Pin actuator rod 236 Pin shaft 238 Pin screw threads 239 Pin head 240 Vane 242, 243 Battens 245 Vane material top end 246 Vane material bottom end 247 Stitching 248 Fastener (staple) 249 Pocket material 250 Stitching 252 Elongated projections (keys) 253 Shaft grooves 260 Flexible shaft 261 Clutch 262 Clutch tube 263 Clutch serrations 264 Clutch grooves 265 Clutch actuator 266 Clutch collar 270 Bend in shaft 260 271 Bearing elements 272 Cross pieces 273 Bearing 274 Cross piece 276 Main vane support 277 Removable fastener 278 Opening in 276 279 Opening in shaft 17 280 Spoke 281-281C Vanes 282 Bottom vane support 283 Third from bottom vane support 284 Vane support 286-288 Vertical supports 290 Quick release fasteners 292-294 Openings for 290s 296 Main vane support 297 Openings in 296 298 Spring pressed pins for operative position 299 Spring pressed pins for inoperative position 300 Spokes 301 Pivot pins 302 Pivot movement stop 303 Vanes 304 Tabs 305 Bottom edge of vane 306 Male snap fasteners 307 Female snap fasteners 309 Upper spokes 310 Vertical links 311-313 Pivot pins 315 Upper vane 316 Upper vane support 317 Vertical supports 319 Hook fastener strip 320 Loop fastener strip 321 Hook fastener strip 322 Loop fastener strip 323 Vane side edge

FIG. 1 schematically illustrates a perspective view of one exemplary (only) embodiment of a wind turbine watercraft according to the invention. The watercraft, generally illustrated at 10, preferably comprises a multihull (a catamaran is shown, but trimarans, or other multihulls, may be used), e.g. having at least first and second hulls 11, 12. Any suitable multihull may be utilized, however according to one aspect of the invention, a Hobiecat® (e.g. a sixteen-eighteen foot Hobie)—one of the most common and practical catamarans in the world—is retrofit with a wind turbine in place of the mast and sail.

The catamaran illustrated in FIG. 1 includes fore and aft crossbars 13, 14, and a vertical axis wind turbine 15 mounted on or adjacent the fore crossbar 13, near where a conventional main sail would be. The wind turbine may be any suitable type, lift, drag, or other. The turbine 15 actually schematically illustrated in FIG. 1 is one commercially available from Oy Windside Production Ltd. of Finland (e.g. a WS-2B model), and is referred to hereafter as a “sculptured” wind turbine. However, for cost or other reasons other vertical axis wind turbines may alternatively (or additionally) be used, including (without limitation) Savonius (either conventional or the novel modified Savonius configurations according to the invention), Giromills, feathering or curved vane (as seen in mechanisms 615 and 614 of “1800 Mechanical Movements And Devices”, ©1911, 2000, Algrove Publishing Limited), dosed helical (as seen in U.S. Pat. No. 6,293,835), reefable rotorsail (as seen in U.S. Pat. No. 4,274,011) or Darrieus vertical axis wind turbines.

If the watercraft 10 comprises a trimaran, two wind turbines 15 may be utilized, one between each of the side hulls and the center hull. Alternatively, extra wind turbines can be mounted outside each of the hulls of a catamaran, or outside the side hulls of a trimaran. Other numbers of wind turbines 15 may be utilized for other multihull configurations.

FIG. 2 is a front view of a conventional sixteen-foot Hobiecat®, including a sail mount on the fore cross bar 13, a dolphin striker post 68, and a dolphin striker rod 69. As shown in FIG. 3, a front view of a Hobiecat modified to receive a vertical axis wind turbine as according to the invention, an aluminum, hard plastic, or other rigid relatively corrosion-resistant material, tube 16 is welded or otherwise affixed to the fore cross bar 13 and the dolphin striker post 68 and/or dolphin striker rod 69. A shaft 17 driven by the turbine 15 is removably received within the tube 16, and at least one bearing 18 is provided for mounting the shaft 17 for rotation about a generally vertical axis. The at least one bearing 18 preferably is a self-aligning bearing having a minimum (shaft) inside diameter of about one inch, with a moisture-proof seal, and capable of taking the dead weight (axial thrust and side loads) of the wind turbine 15. Some possibilities include a Fafnir Type RCJ P1, and a Seal Master MSFT-16C or LFT-16C.

FIG. 4 is a schematic assembly drawing of the preferably releasable/removable mounting of the tube 16 support structure for the vertical axis wind turbine shaft 17, gearing, and propeller, while FIGS. 5-7 show details of an exemplary lower gearing assembly and “clutch” mechanism for driving a conventional boat propeller; and details of an exemplary propeller drive gear assembly and propeller are illustrated in FIG. 8. However other drive mechanisms, as illustrated in other drawings and discussed below, such as vertical axis propellers, paddle wheels, and flapping or oscillating drives, may be utilized.

The brackets 19 and/or other structures for mounting the tube 16 are not critical, and may be of any conventional construction that performs the function of properly mounting the tube 16. The bearing 18 must be suitable for supporting the shaft 17 for low friction rotary movement, and be durable and water proof. Alternatively, the tube 16 may itself be the bearing (if it has a low friction coating or material on the interior, such as PTFE), but desirably the tube 16 is merely a mounting structure. The shaft 20 extending downwardly from the tube 16 may be integral with (e.g. a continuation of) the mounting shaft 17 for the wind turbine 15 or simply attached thereto (by any conventional mechanism) for rotation therewith.

The tube 16 and brackets 19 are mounted in such a way that they do not adversely affect the normal insertion of a conventional mast in the existing mast support on the Hobiecat. Therefore, after removal of the wind turbine 15 and associated driven structures (and the tube 16 and brackets 19 if necessary), the catamaran 10 may be used as conventionally for sailing.

The shaft 20 has external splines 21 [see FIG. 7, a detail cross-sectional view of the shaft] in the preferred embodiment illustrated where the “dutch” is a simple lift plate for the gear 22 driven by the shaft 20.

The reciprocal gear and clutch assembly 23 [see FIGS. 4-7] includes the gear tube 25, which is preferably integral with the gear 22, and rotates the gear 22. The external diameter (including splines 21) of the shaft 20 is less than the internal diameter of the gear tube 25. In the embodiment illustrated, the gear tube 25 has an internal spline configuration 26 [FIG. 7], to cooperate with the splines 21 on the shaft 20 so that rotation of the shaft 20 effects rotation of the tube 25 and gear 22, yet the tube 25 is vertically reciprocal with respect to the shaft 20. The tube 25 has a gear tube collar 27 of significantly larger diameter than the tube 25 itself, and the under-surface 28 [see the exploded view of FIG. 5] thereof is preferably of a low friction material, or coated with such a material, such as PTFE, so that if the surface 28 engages the surface 29 [FIGS. 5-6] rotation of the gear 22 will not be significantly retarded. The gear 22 may be a spur gear, or a conical gear, or a worm gear, but preferably is a bevel or miter gear as illustrated. The gear 22 may be made of aluminum, nylon (or other hard plastic) or other lightweight and/or corrosion resistant material. The gear 22 is a drive gear and must mesh properly with the driven gear 30 [FIGS. 4 & 8] connected to the propeller 45 to drive the driven gear 30. The driven gear 30 may be of any configuration which meshes properly with the gear 22 (e.g. 30 is a bevel or miter gear when gear 22 is a bevel or miter gear).

The “clutch” mechanism of the assembly 23 includes the clutch plate or bar 31 [FIGS. 5-6] having low friction top surface 32, the pivot pin 33, the support plate 34, and the operating lever 35. The forked front end 36 of the clutch plate or bar 31 has a cutout portion with a width 37 that is greater than the outside diameter of the gear tube 25, but less than the diameter of the collar 27. When the pivot pin 33 is pivoted by the lever 35, the clutch plate or bar 31 moves upwardly so that the surfaces 32, 28 engage, and the collar 27 and attached tube 25 and gear 22 are lifted out of contact with the gear 30 [which is not vertically movable]. The lever 35 is preferably operated by a handle portion 47 thereof located [see FIG. 1] where the rudders 64 of the catamaran are operated. At the operation location there is a surface 24 that the handle portion 47 rests on. A strap 48 or functionally similar mechanism can be provided to “latch” the handle portion 47 of the lever 35 in a position where the element 31 front end 36 has been elevated (and thus the gears 22/30 disengaged).

That is, according to this aspect of the invention there is provided a drive wherein a lever operated moving mechanism comprises a collared gear tube 25 connected to a first gear 22, and a generally fork-shaped plate or bar 31 substantially surrounding the gear tube 25 and engaging the collar 27 between the collar and first gear to move the first gear and gear tube along the splined shaft 20.

If desired, a stop 38 is provided on the mounting plate 34 to stop downward movement of the plate/bar 31 so that it cannot engage the gear 22. Also, a spring bias may be provided to bias the element 31 into contact with stop 38. For instance in the exemplary embodiment shown, the coil spring 39 acts between the shelf 37 of the plate 34 and the plate/bar 31 to bias the element 31 into contact with the stop 38. The mounting plate 34 can be mounted to the pontoons of the catamaran by a bracket, which bracket may also mount the bearing/shaft mount 40 [see FIG. 8].

Instead of the top surface 32 of clutch plate 31 being of low friction material, it can be of high friction material, such as used in commercial brakes, so that it functions as at least a partial brake. The collar 27 undersurface 28 also may be made of high friction material. In this way, the rotation of the shaft 20 to which the gear tube collar 27 is keyed is slowed. This may make re-engagement of the gears 22, 30 associated with the clutch easier. With this construction, the clutch assembly 23 acts as both a clutch and a brake (at least a partial brake).

As yet another alternative, instead of a clutch, a brake per se is provided. The brake may be of any conventional friction brake construction for stopping rotation of the shaft 17120, e.g. by clamping a predetermined (e.g. roughened) portion of the outer surface of the shaft 17/20 with a conventional high friction material attached to a mechanical or fluid (e.g. hydraulic or pneumatic) actuator.

The assembly 41 is the propeller drive assembly, and includes a gear 30 integral with the shaft 42 [FIG. 8], which passes through a mount or bearing 40. A “universal” joint connection (such as a conventional simple U-shaped element surrounding the end of shaft 42 and connected by a pivot pin thereto) 43 may be provided to connect the driven gear shaft 42 to the propeller shaft 44. Shaft 44 is integral with or rigidly attached to the propeller 45. A mount or bearing 46 is also provided for the shaft 44. Brackets (see FIG. 9 for one example) also mount the element 46 to the hulls of the catamaran, perhaps even by the same bracket that mounts elements 34 and/or 40. The propeller 45 is preferably aluminum, and has a large pitch (i.e. greater than nine inches) so that even when the shaft 44 is rotated at slow speed (the Savonius wind turbine is a slow rotational speed/high torque driver), the catamaran will be propelled forward at a suitable speed.

The literature suggests a desirable shaft 44 angle β to the surface of the water [see FIGS. 4 & 8] of about 10-16 degrees (about 10 degrees is likely optimum). This shaft angle β may be obtained by any other conventional means aside from what is illustrated in the drawings. For example, cooperating concave face drums on oblique shafts may be utilized, such as illustrated at movement 112 of “1800 Mechanical Movements And Devices”, ©1911, 2000, Algrove Publishing Limited.

The horizontal propeller 45 is of conventional boat design, but preferably has a pitch as large as practical since boat speed is directly related to pitch. For example where the shaft 44 has a diameter of about one inch, the propeller 45 may have a diameter of about ten-fourteen inches (e.g. about 11 or 12 inches), and a pitch of about sixteen inches. The gears 22130, may have any gear ratio desired for optimum operation given the type and size of the wind turbine 15 utilized. For example, the gear ratio of the gears 22/30 may be between about 4:1 to about 1:1 (e.g. about 2:1 or 3:1). A gear ratio of 1:1 may be particularly desirable.

FIG. 9 is a front cross-sectional (taken along shaft 44) schematic view, of one form exemplary brackets 50 could take for supporting one or more mounts or bearings 46 for guiding shaft 44 rotation. A similar arrangement may be provided for supporting the bearing or mount 40. Each bracket 50 has one or more struts 51 affixed (e.g. removably, as by bolts or screws) to the outside of a bearing or mount 46, and a generally U-shaped portion 52 that fits over one of the hulls 11, 12 of the catamaran 10. The portions 52 of the brackets 50 may be held in place by friction with a hull 11, 12, a conventional removable fastener, cooperating hook and loop (e.g. VELCRO®) fasteners, or any other suitable conventional mechanism. Preferably the portions 52 are readily removable from the hulls 11, 12 to allow (after detachment of the wind turbine 15 and shaft 20 and associated gear 22) the catamaran 10 to be used for sailing.

Also, the brackets 50 and related supports are removable so that the entire gear 30, shaft 44, and propeller 45 assembly 41 may be removed from the watercraft 10 when docked. At the dock, an electric generator, pump, or other device commonly driven by a wind turbine, may be operatively connected to the gear 22 instead of just moving the gear 22 out of engagement with the gear 33 using the clutch of the assembly 23. If desired, the wind turbine 15 can instead be covered with a cloth or housing when docked so that it does not rotate, or wind turbine 15 can simply be removed from the watercraft 10 and placed on the ground or in a shed.

As seen in FIG. 10, a front hydrodynamic cover 54 may be provided for the gears 22, 30 so as to minimize resistance as the watercraft 10 moves through the water. The cover 54 may be connected by struts (not shown) to the same brackets as support the mount or bearing 40, or one or more tapered front edge struts 55 may connect the cover 54 to the gear tube 25.

As many of the components possible as possible are preferably made of aluminum or a suitable plastic (e.g. nylon), so as to minimize weight and degradation thereof in a water environment. The gears 22, 30 should be made of a material that is self-lubricating, or lubricated by water, or at least so that the gears can function in a water environment with minimal difficulties.

In use, the wind turbine 15 drives the shaft 17 supported for rotational movement by the bearing 18 and/or tube 25, which in turn drives the splined shaft 20 and the gear 22. The gear 22 drives the gear 30 and shaft 44, which in turn rotates the propeller 45, driving the catamaran. To stop the driving action, the lever 35 is simply pivoted downwardly, rotating the plate or bar 31 about pivot pin 33 and lifting the gear 22 out of engagement with the gear 30. By slowly lowering the lever 35, the gears 22, 30 may be re-meshed (although it may be necessary to stop or slow the wind turbine before doing that). The catamaran may be steered merely by the already existing rudders 64, and there is no need to “sail” the craft because the direction of the wind is irrelevant. Except for the effect of the force component of the wind on the actual “body” of the craft 10, it moves into the wind at the same speed as with the wind, or perpendicular to it.

If it is desirable to provide a reverse gear for the watercraft 10, the assembly illustrated in FIG. 11 may be utilized. In this embodiment the shaft 20 continues past the gear 22 and is splined to the gear 57. Also, a nut, or other type of cap, 58 is provided on the bottom end of the shaft 20 below the gear 57 so that the gear 57 is lifted when the collar 27 is lifted by lever 35. Where the gears 22, 30 are bevel or miter gears, so is the gear 57. The gear ratios for the gears 30, 57 may be different than for the gears 22, 30 since the reverse speed need not be the same as the forward speed. For example (again depending up the particular wind turbine 15 and other factors) the gear ratio of the gears 30157 may be about 1:1.

Any suitable conventional detent mechanism (shown only schematically at 59 in FIG. 11) may be provided to detent the lever 35 in different positions. For example the normal or “forward” position would be where the gear 22 is biased by gravity (with an optional spring assist—such as the coil spring 60 illustrated schematically in FIG. 11) into contact with the gear 30, a “neutral” position in which neither of the gears 22, 37 operatively engages the gear 30, and a “reverse” position in which the gear 57 operatively engages the gear 30. All of the gears 22, 30, 57 may be constructed so that they easily mesh together when brought into engagement, even when the shaft 20 is rotating.

The gearing arrangement in FIG. 11 may be replaced by equivalent gearing arrangements, such as movement 977 of “1800 Mechanical Movements And Devices”, ©1911, 2000, Algrove Publishing Limited. Also, the gearing arrangements of FIGS. 4 and 11 are not limited to water turbine watercraft, but have numerous other applications.

Instead of a generally horizontal propeller 45, a vertical propeller (shown schematically at 62 in FIG. 12) may be utilized, connected to the shaft 20 either directly, or through gearing (shown in dotted line at 63 in FIG. 12) if the propeller is to be driven at a different speed than the shaft 20 rotates. Non-limiting examples of vertical propellers are the commercial Voith-Schneider propeller (examples of which are shown in U.S. Pat. Nos. 5,588,798 and 4,225,286), and the propellers shown in U.S. Pat. No. 5,462,406, or 6,244,919, all of which are incorporated by reference herein.

Other types of propulsion mechanisms aside from propellers may alternatively or additionally be utilized. For example, the foot pedals in U.S. Pat. No. 5,022,249 (incorporated by reference herein) may be replaced by crank arms connected through gearing to the shaft 20, to provide a “penguin-like” propulsion action. Or the novel per se propulsion mechanism according to the present invention as illustrated in FIGS. 13-20 may be used.

FIG. 13 is a side schematic view of an exemplary propulsion system 70 according to this aspect of the invention shown hooked up to the wind turbine 15 of FIG. 1. However, it is to be understood that the propulsion system 70 of FIGS. 13-20 (in its various forms) may be used for human powered (hand or leg or both), electric motor-powered, or fossil fuel powered watercraft of any type.

The basic feature of the system 70 is that it roughly simulates a fishtail, or sculling, action. FIG. 14 is a bottom view of the system 70, while FIGS. 15-17 are detail top views of the individual components 71-73, respectively. FIGS. 18-20 are schematic top views of other forms of the propulsion system 70, having different components, but with the same basic operating principle. Other forms are also possible for turning rotary movement into oscillation of a “flipper”, such as are illustrated as movements 960 and 1032 of “1800 Mechanical Movements And Devices”, ©1911, 2000, Algrove Publishing Limited.

The main components of the propulsion system 70 of FIGS. 13-17 are a drive element 71 connected to the shaft 20 for rotation therewith, a guide element 72, and an oscillating “flipper” 73. The drive element 71 may be a crank arm, as illustrated, or a disc, or of other shape. The square or other non-round hole 74 (FIG. 15) adjacent one end of crank arm 71 (or in the center thereof if a disc) is connected to the shaft 20 for rotation therewith. The hole 75 adjacent the other end of arm 71 receives a pivot pin 76. The pin 76 in turn is received by the hole 77 (FIG. 17) in the first end 78 of the oscillating element 73, so that the elements 71, 73 freely pivot with respect to each other.

Preferably, an elongated slot 79 (FIGS. 14 & 16) is formed in the guide element 72 (but another lost motion mechanism may be provided instead). The element 72 is mounted stationary to the watercraft 10, for example by bracket 80 as illustrated in FIG. 13. The slot 79 receives a pivot pin 81, which is pivoted to the oscillating element 73 at the middle opening 82 (see FIG. 17) thereof. The pivot pin 81 defines a generally vertical axis about which the element 73 is pivoted by the crank arm 71, and the pivot axis translates along the slot 79. The slot 79 may be defined by a highly polished surface (e.g. where the guide element 72 is of aluminum or another metal), or a coating, treatment, or insert of low friction material (such as PTFE) may be provided, to allow ready translation of the pivot pin 81 in slot 79 while the element 73 freely pivots with respect to the element 72. An optional spring (illustrated only schematically in dotted line at 83 in FIG. 17) may be provided at one or both ends of the slot 79. The spring 83 may be a coil spring, compressible material, or have any other conventional construction.

The pivot pin 82 may have a cap 84 at the end thereof remote from the element 73 to prevent it from inadvertently moving out of the slot 79. The cap 84 may have a low friction bottom surface, in case it inadvertently slides along the top surface of the element 72 (if the components have the orientation illustrated in FIG. 13). Another cap 85 (like cap 84) larger than the slot 79 width is desirably below the element 73. As some of several alternatives, the guide element 72 may be mounted below the oscillating element 73 instead of above it, and the pivot pin 82 may be attached to the guide element 72, and the elongated slot 79 provided in the oscillating element 73.

The oscillating element 73, at the free end 86 thereof, remote from the first end 78, is formed to roughly simulate a fish tail fin, or a sculling oar water-immersed end. While the free end 86 may be of the same relatively rigid material (e.g. aluminum or hard plastic) as the rest of the element 73, desirably the end 86 is defined by a core 65 of rigid material (e.g. aluminum or hard plastic), with a covering 66 of relatively flexible material, such as natural or synthetic rubber, or flexible plastic. The covering 66 is shown as transparent in FIG. 13 for clarity of illustration, but it may be opaque. The end 86 covering 66 may have the durometer (e.g. between about 40-100, e.g. between 60-90 as in U.S. Pat. No. 4,017,925, incorporated by reference herein), and/or have the flexible properties, of a conventional scuba diver's flipper. The covering 66 may be formed as a sleeve which fits over the termination of the rigid portion of the element 73 end 86, and attached by adhesive, a friction fit, or other standard attachment means, thereto. The covering 66 may also have one or more supporting ribs 67 at various locations, such as dihedral ribs. The core 65 merely provides support, and does not need to have the fishtail or scull (“oar”, definition 1, Random House Unabridged Dictionary, 2^(nd) Edition, ©1987, 1993) simulating shape of the covering 66.

Especially when connected up to a vertical axis wind turbine 15, the oscillating element 73 preferably has a range of oscillation (see γ in FIG. 14) of between about 10-45 degrees. If a motor powers the drive element, then the oscillation angle may be greater.

In the FIGS. 18-20 embodiments of the propulsion system 70, instead of a crank arm and guide element, a cam and cam follower arrangement is provided. FIGS. 18 and 19 show the two extremes of an embodiment in which a cam 90 operatively connected to shaft 20 for rotation therewith has a plurality of lobes 91, which engage a cam follower 92. The follower 92 is at a first end of an oscillating lever 93, pivoted at 94 to a stationary (with respect to the watercraft 10) support (like the plate 72, but not shown). The lever 93 portion 95 on the opposite side of pivot 94 from follower 92 is at an angle α with respect to the portion 96 between the pivot 94 and follower 92. The angle α is preferably between about 5-25 degrees, e.g. about 12 degrees, so that the extent of oscillation of element 73 is between about 10-50 degrees. The portion 95 is preferably constructed like the end 86 of the FIGS. 13-17 embodiment, that is it may be rigid, but preferably has a rigid base to which is mounted a flexible fishtail-simulating element (66).

In the FIG. 20 embodiment, the cam 98 is operatively connected to the shaft 20 for rotation therewith, and has a cam track 99 formed on the top surface thereof. A follower 100 on one end 97 of the oscillating lever 101 moves in the track 99, and causes the lever 101 to oscillate about stationary pivot point 102. The free end 103 of lever 101 has a fishtail-simulating element as previously described.

In all of the FIGS. 13-20 embodiments, it may be desirable to provide a disconnect between the propulsion mechanism and the drive (e.g. wind turbine 15). Any suitable conventional disconnect may be utilized. For example, as schematically illustrated at 104 in FIG. 13, a simple dutch mechanism in shaft 20 may be disengaged manually (e.g. by a lever, not shown, located near the rudder control for watercraft 10), or electronically or by other remote control, to detach the wind turbine 15 from the crank arm 71 (or the cams 90, 98 in the FIGS. 18-20 embodiments). While any simple conventional clutch may be used, particularly desirable are claw and geared clutches, such as shown on pages 206-7 of “How Things Work”, infra.

Under some circumstances—such as if there are low-wind conditions, or at start-up—it is desirable to provide a manual assist to the wind turbine for rotating the shafts 17/20 (or in some cases one of the shafts 42, 44). Such an assist is illustrated very schematically at 105 in FIG. 13; it may be hand, foot, head, or otherwise operated. The assist 105 may comprise a mechanism such as used for pull-cords for starting internal combustion engines (such as shown in U.S. Pat. Nos. 4,103,660, 5,762,037, 5,174,166, and 5,253,540, incorporated by reference herein), or for pedaling motorized bicycles (such as shown in U.S. Pat. Nos. 4,085,814 and 5,242,028, incorporated by reference herein), an assist for a wheelchair (such as shown in U.S. Pat. No. 6,302,226, incorporated by reference herein), or a paddlewheel mechanism (such as shown in U.S. Pat. No. 5,058,522, incorporated by reference herein), or such as illustrated at movement 1000 of “1800 Mechanical Movements And Devices”, ©1911, 2000, Algrove Publishing Limited. One particular embodiment is illustrated schematically in FIGS. 21 and 22.

The basic assist 105 illustrated in FIG. 21 is as shown in FIG. 2 of “How Things Work”, Segalat, Vol. III, page 213, Simon + Schuster; including: a ratchet wheel 106 connected to the shaft 17 for rotation therewith, a drive pawl 107 biased by a leaf spring 49 into contact with ratchet 106 and pivotally mounted to a lever 108; a catch pawl 109 biased by a leaf spring 53 into contact with the ratchet 106 and pivotally mounted to a support structure 110 on the watercraft 10 that is stationary with respect to the shaft 17; and a coupler 111 pivoted at one end there of to the lever 108 and at the other end thereof to a crank arm 112. However, in the FIG. 21 embodiment, the crank arm 112 is rotated manually about a pivot 113 on support 110 in a generally horizontal plane, using the knob/handle 114. The adjustment slot illustrated on page 213 of “How Things Work” may or not be provided. The knob/handle 114 is preferably connected to the crank arm 112, but it may be connected to the point of connection of the coupler 111 to the crank arm 112, especially where an adjustment slot is provided.

When the knob 114 is rotated about a generally vertical axis, the manual assist 105 unidirectionally rotates the shaft 17 in the same direction as the wind turbine 15 does, and does not significantly interfere with the rotation of the shaft 17 when the manual assist 105 is not used. However, to insure no drag whatsoever by the pawl and ratchet arrangement of the mechanism 105, as illustrated schematically in FIG. 22 the pawls may be moved to and held in an inactive position. In FIG. 22 the spring 53 is mounted to the support 110 by a pivot pin 116 extending substantially transverse to the shaft 17. The pin 116 has a high degree of friction with respect to the spring 53 and the support 110 so that it stays in the position to which it is pivoted. However, by hand one on the watercraft 10 may simply rotate the leaf spring 53 about the axis defined by pin 116 from the active position illustrated in FIG. 21 to the deactivated position illustrated in dotted line in FIG. 22. The pawl 109 may also then be pivoted backwardly, and held in a position spaced from the ratchet 106 by any suitable latch, such as the strong elastic band loop 117 [FIG. 21] affixed to the support 110.

Alternatively, the band loop 117 may have a spring constant greater than that of the leaf spring 53, and when stretched and placed on the pawl 109 may hold the pawl in an inactive position even though the leaf spring 53 still engages the pawl 109. Alternatively, any suitable conventional mechanism may be used that performs the function of “deactivating” the pawl 109. The pawl 107 may have the same type, or a different type, of deactivating mechanism as the pawl 109. In any event, when the pawls 107, 109 are deactivated, then do not provide any drag on the shaft 17 when the manual assist 105 is not being used.

According to another aspect of the present invention, modified forms of a Savonius wind turbine, the modified forms being indicated generally by reference numeral 120 (see FIGS. 23 and 24), or 121 (see. FIGS. 25 and 26) are provided. One of the wind turbines 120, 121 is preferably used as the wind turbine 15 in the watercraft 10, but is not restricted for such a use. Rather, the wind turbines 120, 121, may be used anywhere that a vertical axis wind turbine is desirable or functional. In both embodiments the modified Savonius wind turbine of the invention comprises a pair of opposite curved vanes connected together by a perforated central shaft which allows spillover from one vane to the other to increase efficiency.

The modified Savonius wind turbine 120 of FIGS. 23 and 24 has the strength advantage of a conventional central shaft Savonius design, while at the same time having most of the enhanced-efficiency advantages of the overlapping vane designs. The conventional central shaft and overlapping vane Savonius designs are shown in “Making a simple Savonius wind turbine” by Lance Turner, viewable at www.ata.org.au. While the vanes 122, with end terminations 128, in FIG. 23 are shown shaped as in the second Turner design, they may alternatively be shaped as in the third Turner design, as seen for vanes 123 (with end terminations 129) in FIG. 25. In any event, a perforated central shaft is provided, shown by reference numeral 125 in FIGS. 23 and 24, and 126 in FIGS. 25 and 26. The shafts 125, 126 are, or are part of, the shaft 17 of the earlier figures.

The perforations 127 in the shaft 125 may be of any suitable construction, such as the substantially vertically elongated slots illustrated in FIG. 24, having a spiral or curvilinear configuration, or in the form of round or polygonal holes. Depending upon how securely the vanes 122 can be attached to the shaft 125, vane supports substantially perpendicular to the shaft 125 need not be provided, or may be minimized (e.g. only at the top and bottom of a sixteen foot high, three foot diameter, active surface wind turbine 15 for a sixteen foot Hobiecat catamaran).

The shaft 125 may be made of PVC (or other plastic, including fiber-reinforced plastic) or aluminum pipe with optional passage-defining hollow elements 130 extending between cooperating perforations 127 on opposite sides of the shaft 125. Alternatively, the shaft 125 may be solid, with the perforations 127 through-extending bores (e.g. formed by drilling or machining) therein. The vanes 122 may be sheet metal, corrugated plastic, or a like material that is lightweight and relatively corrosion-resistant, yet will withstand significant wind forces, or may be woven polyester cloth or other “sail” grade cloths. The shaft 125 and perforations 127 are constructed/provided to supply sufficient support for the vanes 122 in the wind conditions expected to be encountered, while allowing significant “spillover” from one vane to the other to increase efficiency.

In the FIGS. 25 and 26 embodiment, the vanes 123 have substantially planar end portions 131. These may be securely affixed to the central shaft 126 by providing cooperating flat side surfaces 132 for the shaft 126. For example, the entire shaft 126 where connected to vanes 123 may have a polygonal (preferably substantially square) cross-section with perforations 133 extending substantially parallel to the surfaces 132. Alternatively, the shaft 126 may be circular in cross-section, and the portions thereof to be affixed to the end portions 131 flattened. Attachment of the portions 131 to the shaft 126 surfaces 132 may be by welding, mechanical fasteners, adhesive, or other conventional means. The perforations 133 also may have a wide variety of shapes (see the side view, partly in cross-section and partly in elevation, of FIG. 26), and the perforations 133 on opposite sides of the shaft 126 may be aligned (the round holes 133 in FIG. 26), or offset (the slots 133 in FIG. 26).

FIGS. 27-29 illustrate another—and preferred—embodiment of a manual assist 134 according to the present invention. The basic operational components of the FIGS. 27-29 embodiment are basically the same as illustrated and described in U.S. Pat. No. 5,072,929, the disclosure of which is hereby incorporated by reference herein. The components are primarily mounted on one of the hulls 11, 12, e.g. the hull 11 as seen in FIGS. 27 and 28.

Mounted on the top of hull 11, near the stern thereof, are one or more rails 135 (only one will be described) on which a seat 136 can slide back and forth. When the manual assist 134 is not used, the seat 136 is moved to a position in which the opening 137 in the rail 135, and the opening 138 in a flange 139 extending downwardly from the seat 136 are aligned, and a lock pin 140 is inserted through the openings 137, 138. When the lock pin 140 is in the openings 137, 138, the seat 136 cannot slide on the rail 135, but the operator 141 can still use the seat 137 for comfort when moving along under only wind power.

The manual assist 134 as illustrated has two drive assemblies 142, 143 so as to allow the operator 141 use of both primarily arms [drive assembly 142] and primarily legs [drive assembly 143] to power the craft 10. However, only one assembly need be provided.

The first drive assembly 142 comprises a support arm 144 mounted to the rail 135, or otherwise on or near the top of the hull 11, which mounts a pulley 145 or other low friction element that allows the ready reciprocation of a first cord 146. At a first end thereof, the first cord 146 is connected to a handle 147 which the operator 141 grabs. At a second end thereof (as seen schematically in FIGS. 28 & 29) the first cord 146 is connected to a first cord drum 148, mounted on the vertical shaft 17, 20 of the wind turbine 15. The first cord 146 is made of substantially inextensible material, such as (without limitation) a steel cable covered with a plastic sheath.

The first cord drum 148 is mounted to the shaft 17, 20 by a one-way, freewheel, dutch, shown schematically at 152 in FIG. 29. The dutch 152 may be any suitable, conventional, one-way clutch, such as shown in U.S. Pat. Nos. 3,844,391 or 4,746,112, or used in the THYS 222 Rowingbike commercially available from BCBikes.com. During a power stroke by the operator 141 (i.e. pulling the handle toward him/her with his/her arms) the clutch 152 allows the cord 146 to power the shaft 17,20 in the same direction of rotation as the wind turbine 15. When the drum 148 returns after tension on the cord 146 is released by the operator 141, the dutch 152 allows drum 148 to freewheel and take up the cord 146. The first cord drum 148 is biased—e.g. by the torsion spring 149 shown schematically in FIGS. 28 & 29, or an elastic band, or other suitable conventional biasing device (such as the recoil mechanism shown in U.S. Pat. No. 4,746,112)—so as to take up the cord 146 on the drum 148 after release by the operator 141.

The assembly 142 further comprises a pulley 150 (FIGS. 27 & 28), or like low friction, direction-changing device, mounted for rotation on or with a shaft 151. The shaft 151 preferably is provided on the fore crossbar 13, over the hull 11. The pulley 150 redirects the force on the handle 147 during the power stroke to rotation of the shaft 17, 20 as the cord 146 is taken off the drum 148, and redirects the take-up force provided by spring 149 to move the handle 147 toward the support arm 144 as the cord 146 is being taken up on the drum 148 during the release stroke.

The second drive assembly 143 is powered primarily by the operator 141's legs, not arms. The assembly 143 includes a second cord 154 of substantially inextensible material mounted at one free end thereof to the reciprocal seat 136. While in FIG. 27 the cord 154 is shown mounted to the bottom of the flange 139 extending downwardly from the seat 136, that is not necessary. The cord 154 may be mounted to any part of (or extension of) the seat 136 as long as it does not significantly interfere with reciprocation of the seat 136 along the rail 135, the hull 11, and the operator 141. For example, the cord 154 may be mounted to the front face 155 of seat 136 (see FIG. 28), in which case the flange 139 need extend downwardly from the seat 136 only far enough to provide the opening 138, and does not overhang the inner starboard face of the hull 1 (as it does in FIG. 27).

The second cord 154 may pass around two pulleys—one not shown, and the other shown at 156 in FIG. 27—mounted on the support arm 144. From the pulley 156 the cord 154 extends to the pulley 157 mounted on shaft 151 below pulley 150, to a second cord take-up on the shaft 17, 20. As seen in FIG. 29, a second cord drum 158 biased by spring 159 and mounted to shaft 17, 20 by a second one-way clutch 162, are provided. The drum 158, take-up (e.g. spring) 159, and clutch 162 may be substantially identical to (in structure and operation) the corresponding devices 148, 149, 152 associated with the first cord 146.

During a power stroke associated with the second drive assembly 143, the operator 141 places his/her feet on the support plates (only one of which is shown in FIG. 27) 163 operatively mounted to hull 11 (e.g. connected to support arm 144), and pushes with his/her legs. This moves the seat 136 aft along the rail 135, unwinding the second cord 154 from the drum 158 and rotating the shaft 17, 20 in the same direction that the wind turbine 15 rotates it. Once the end of the power stroke is reached, the operator 141 moves his/her body fore (e.g. with the assistance of the straps 164 holding his/her feet to the foot plates 163) and the seat 136 moves fore, with the spring 159 taking up the cord 154 on the drum 158 while the clutch 162 allows the drum 158 to freewheel on the shaft 17, 20. When manual assist 134 is no longer necessary (e.g. when the wind picks up so that turbine 15 alone adequately powers the craft 10), the operator 141 slides the seat 136 to an aft position in which the openings 137, 138 are aligned, and inserts the lock pin 140 through them to hold the seat 136 stationary. In this position, the handle 147 will be biased against the support arm 144 by the spring 149. The spring 159 will be taught, however, unless (e.g. using a quick release fastener, such as a Caribiner or clasp on cord 154 and a hook on seat face 155) the cord 154 is detached from the seat 136, in which case the cord 154 also will be moved to stop against arm 144.

The rail 135, support arm 144, and foot plates 163 may be mounted by any conventional mechanism(s), and in any desired orientation, on the hull 1. For example, screw fasteners, adhesive, brackets, and/or quick-release fasteners may be utilized. The rail 135, seat 136, and foot plates 163 may be permanently or removably mounted, regardless of whether the craft 10 is to be used only with a wind turbine 15, or alternatively with a conventional mast. If the craft 10 is to be alternatively used with a mast, preferably the support arm 144, shaft 151 and associated pulleys 150, 157, and the cords 146, 154 and handle 147, are mounted for ready removal.

While the exemplary manual assists described herein have been shown operatively connected to the wind turbine shaft 17, 20, a manual assist may be provided connected directly to the propeller shaft 44 when a horizontal propeller 45 is used as the propulsion mechanism. Also, even though still referred to as a “manual assist”, the manually powered mechanism may be typically used to provide more than half of the drive force for the watercraft 10, with the vertical axis wind turbine 15 then typically providing less than half. In that circumstance, the wind turbine 15 would have dimensions, and be constructed, so that it was smaller than if it typically would provide the majority of the drive force for the watercraft 10.

FIG. 30 is a schematic illustration of a propulsion mechanism for the craft 10 that is an alternative to the propellers 45, 62, or fishtail system 70. In FIG. 30 a drive gear 170 is connected to the wind turbine shaft 17, 20, and cooperates with a face gear 171 concentric with and connected to a first paddle wheel 172, and a reversing gear 173. The reversing gear 173 also cooperates with a face fear 174 concentric with and connected to a second paddle wheel 175. The paddle wheels 172, 175 are mounted by any suitable conventional means (not shown) between the hulls 11, 12 for rotation about horizontal axes (or a substantially common horizontal axis). As is conventional for paddle wheels, the wheels 172, 175 are mounted so that with normal loading of the craft 10 they are approximately half in and half out of the water.

FIG. 31 illustrates a vertically collapsible form of wind turbine 215 that may be mounted on a multihull craft 10 as the turbine 15, according to the invention, or may be used anywhere that a wind turbine is useful. The wind turbine 215 of FIG. 31 has an open helix construction, but merely be rearranging the relative orientation of the vane supports and the design of the vanes thereof (as hereinafter described) the same basic structure can be used for a Savonius wind turbine, as seen in FIGS. 35 and 36. The vane supports and shaft 17 are common in FIGS. 31-36 and will use the same reference numerals. The configuration of the vanes is different in FIG. 31 on one hand, and FIGS. 35 & 36 on the other, and will use different reference numerals.

There are many instances in which a vertically collapsible vertical axis wind turbine 215 is desirable. Whenever it is desired to quickly deactivate the wind turbine—such as at a dock if the turbine 215 is mounted on a multihull craft 10, or when damaging high winds exist in land-based environments—a collapsible design is suitable. The vertically collapsibility of the turbine 215 is provided by the use of spaced vane supports, and flexible vanes.

In the embodiment illustrated in FIGS. 31-36, a plurality of vane supports 220, 221, and 222 are provided on a substantially vertical shaft 17. The shaft 17 may be connected to a propulsion system when used on a watercraft 10, or to a pump, generator, or other suitable mechanism when on land. While three vane supports 220-222 are illustrated in the drawings, it should be understood that two, four, or more, may be provided on a given shaft 17.

In the embodiment of the vane supports illustrated, each vane support 220-222 is illustrated as having four spokes 223, 224, 225, and 226, a central hub 227 having a concentric substantially vertical (during use) central bore 228, and for at least the vane supports 220, 221 a substantially horizontal (during use) bore 229 extending from the exterior of the hub 227 to the central bore 228. However, two, three, or more than four spokes 223, etc., may be used depending upon the particular circumstances. Also, more than one horizontal bore 229 may be used. The vane supports 220-222 may be made of any suitable material, one that preferably has high rigidity so that there is little deformation of the spokes 223, etc. during use. Hard plastic (such as Lexan), or lightweight corrosion-resistant metal (such as titanium or aluminum), or carbon fiber reinforced plastic, are examples of suitable materials.

While the spokes 223-226 are illustrated in the drawings having shapes approximating an overlapping vane Savonius design (see “Making a simple Savonius wind turbine” by Lance Turner,), the spokes 223 etc. could have more conventional and/or pronounced curvatures, especially if only two or three spokes are provided on each vane support 220-222.

The turbine 215 is made collapsible by using flexible vanes supported by the spokes 223-226, and by mounting at least the top or bottom vane support 220-221 so that it may be readily moved from an operative position (FIGS. 31 & 35) to a collapsed position (FIG. 36). For example, as seen in FIGS. 31, 35 & 36, the top and middle vane supports 220, 221, are cooperable with locking pins 231, 232 (see FIG. 36), which in turn cooperate with aligned substantially horizontal holes 233 formed in the shaft 17 to hold the vane supports 220, 221 in the operable position (FIGS. 31 & 35).

The pin 231 is shown as a conventional quick release pin which has projections 234 extending outwardly from pin shaft 236 which engage the interior wall of shaft 17 (If the shaft 17 is hollow), or interior cavities of the shaft 17, when the actuator rod 235 is extended, but which move inwardly to a non-engaging position when the rod 235 is depressed. The pin 232 is exteriorly screw-threaded, as indicated at 238, so that it cooperates with corresponding interior threads (not shown) in an opening 233. The head 239 of the pin 232 may have a screwdriver receiving slot, a polygon shape for grasping by a wrench, wings for turning by hand, or another conventional construction. Normally only one type of pin (231 or 232) will be used with a particular shaft 17.

The turbine 215 has as many vanes 240 as spokes 223-226 on one vane support 220-222. A vane 240 is mounted by a spoke 223-226 of each of the vane supports 220-222. For example, the spokes 223 of all of the vane supports 220-222 mount one vane 240, the spokes 224 another vane 240, etc. Each vane 240 is flexible. That is, the vane 240 is of sheet (or like) material that will bend, fold, or otherwise move, to a configuration such as illustrated in FIG. 36. However, the material of which the vane 240 is made is not itself extensible. That is, the material of the vanes 240 is preferably substantially inextensible, such as the material that commercial kites, or high performance sails [e.g. woven polyester, such as Dacron®], are made of, so that the material maintains its shape when impacted by even high velocity wind when in the operable position (FIGS. 31 & 35). Certain types of metal, or metal laminated to cloth and/or plastic, also may be suitable. Also, vertical, horizontal, and/or diagonal stiffening battens (e.g. of hard plastic or metal) may be mounted with the vane 240 material (e.g. in preformed pockets) between the vane supports 220, 21 and 221, 222, when in the operable position (and removed before movement to the collapsing position of FIG. 36). Two such battens—a substantially vertical batten 242, and a substantially diagonal batten 243—are schematically illustrated in dotted line (within the vane 240 material) in FIG. 35.

Exactly how the vanes 240 are connected to the spokes 223, etc., may vary widely. In FIG. 31 an open helical wind turbine is illustrated. That is, the vane support 221 is offset from the supports 220, 222, so that the vane 240 material twists into a helix from the top to the bottom of the shaft 17. In this embodiment, the vane 240 material is simply attached to the spokes 223-226 by a suitable adhesive.

In the Savonius embodiment of FIGS. 35 & 36, the vane 240 material is shown connected to the spokes 223-226 by stitching. For example, the top and bottom ends 245, 246, respectively, of the vane 240 material is wrapped around the spokes 223 (seen most clearly in FIG. 5) of the upper and lower vane supports 220, 222, respectively, and stitched tightly in place by the stitches 247. For the spoke 223 of the central vane support 221, the material of the vane 240 may be attached by one or more fasteners (e.g. staples 248), adhesive, and/or pocket material 249. The pocket material 249—which like the vane material is substantially inextensible—is moved tightly into place into contact with the spoke 223, and then securely held in place by stitches 250.

While not necessary under all circumstances, in order to insure proper alignment of the cooperating spokes of the various vane supports 220-222 [whether making the helix construction of FIG. 31 or the Savonius construction of FIGS. 35 & 36] it is desirable to provide some sort of key between the shaft 17 and hubs 227. For example, as seen most clearly in FIGS. 32 & 33, one or more vertically (during use) elongated projections (keys) 252 are provided extending interiorly from the hub 227 into the central bore 228 on at least the top 220 and center 221 vane supports. The projections are 252 are keyed to the shaft 17 by inserting them into one or more substantially vertically elongated grooves 253 (seen most clearly in FIGS. 35 & 36) in the shaft 17. The number and relative positions of the projections 252 (and cooperating grooves 253) will determine whether various vane supports are offset from others. For the Savonius configuration of FIGS. 35 & 36, the projections 252 in at least the hubs 220, 221 will have substantially exactly the same orientation with respect to the spokes 223-226 so that all of the cooperating spokes are vertically aligned. For the helix configuration of FIG. 31, on the other hand, the projections 252 associated with the central vane support 221 may have a different position with respect to the spoke 223 than the projections 252 associated with the top vane support 220, to provide a “twist” in the vane 240.

The bottom vane support 222 may be substantially permanently affixed to the shaft 17 (e.g. by welding and/or an adhesive), or also may be made slidable and releasably lockable in place like the supports 220, 221.

In use of the turbine 215, when in the operable position, the vane supports 220, 221 are slid along the shaft 217 (preferably with the projections 252 keyed to the grooves 253) until the openings 229, 233 align. Then locking pins (e.g. 231 or 232) are moved into place, locking the hubs 227 of the supports 220, 221 to the shaft 17. The vanes 240 are then taught, and the shaft 17 will be rotated by wind engaging the vanes 240, the force of the wind transmitted by the vanes 240, spokes 223-226, and vane supports 220-222 to the shaft 17. When one returns to the dock, or otherwise does not want the wind turbine 215 to operate, one simply releases the pins 231 or 232 (by hand, or using any suitable tool designed for that purpose). In the illustrated embodiment, this causes the vane supports 220-222 to move toward each other under the force of gravity, from the position of FIG. 35 to that of FIG. 36. That is, the wind turbine 215 collapses so that it no longer effectively functions as a wind turbine.

Instead of being moved manually, a modified form of the pin 231 may be provided that are automatically operated. For example, an electrically powered pin moving mechanism (not shown), such as a solenoid, may be mounted to at least the hub 227 of the top vane support 220 adjacent the hole 229. When a remote control actuator is operated, the powered pin moving mechanism may then move the pin 231 actuator 235, and then the pin 231 itself, to release the pin 231, thereby causing the top vane support 220 to collapse.

While particular mechanisms have been illustrated and described for connection of the vane supports 220-222 to the shaft 17, and the vanes 240 to the vane supports 220-222, it is to be understood that a wide variety of other conventional mechanisms are also possible for such attachments. Any conventional or hereafter developed structures which accomplish the same function are suitable.

FIG. 37 schematically illustrates another form of collapsible vertical axis wind turbine according to the present invention. The major difference between the wind turbine 215′ of FIG. 37 and the wind turbine 215 of FIG. 31 is that only two vane supports 220′, 222′ are provided, each with only three spokes 223′-225′, and the spokes of the various supports are of different lengths. That is, the lengths of the spokes 223′-225′ of the bottom vane support 222′ are less than half the length of the spokes 223′-225′ of the top support 220′. While this results in less surface area of the turbine 215′, the operator of a watercraft on which the device 215′ is mounted would have clearer sight lines at the bottom of the turbine 215′. Further, other vane supports (e.g. two to six more) and vanes may be mounted above the vane support 220′ in FIG. 37, and the portions of the turbine above the support 220′ may have a Savonius configuration rather than the helical configuration for the vanes 240′ illustrated in FIG. 37. Also, the upper vane support can be smaller than the next lowest one so that the upper vanes (where the wind is strongest) have less vane area, so there is less tendency to “tip” if on a craft 10.

While the turbines 215, 215′ may be used on land, they are particularly desirable when used on a watercraft, such as the catamaran 10 shown in FIGS. 38 & 39, having hulls 11 and 12, and crossbars 13, 14. The wind turbine 15 illustrated in FIGS. 38 & 39 is a conventional two component Savonius wind turbine, but the wind turbines 215, 215′ (or other suitable wind turbines) may be substituted.

The most significant novel feature of the FIGS. 38 & 39 embodiment is the use of a flexible drive shaft. Instead of using gears, or other transfer mechanisms, for transmitting the substantially vertical axis rotation of the wind turbine shaft 17 to the horizontal propeller 45, a flexible shaft 260 is provided which—as seen in FIG. 38—is able to bend substantially 75-90 degrees in connecting the turbine shaft 17 to the propeller 45. By using the flexible shaft 260, the losses associated with gearing are eliminated.

The flexible shaft 260 may be constructed as illustrated and described in U.S. Pat. Nos. 4,832,571 or 5,820,464 (which are incorporated by reference herein). The shaft 260 may be integral with the shaft 17—that is, the shafts 17, 260 may be one piece. In such a circumstance, a clutch is not provided, however. Where a clutch is desirable, the shaft 17 may be distinct from the shaft 260, and a clutch 261 (see FIG. 38) provided therebetween.

The clutch 261 may be of any suitable conventional construction. One example, as illustrated in FIG. 40, is to provide a tube 262 keyed to the shaft 17 and having an interior with serrations 263. The serrations 263 cooperate with like grooves 264 on the upper (substantially vertical) portion of the flexible shaft 260. By pivoting or sliding the actuator 265—which cooperates with collar 266 on tube 262—upwardly, the tube moves out of contact with the flexible shaft 260, so that rotation of the shaft 17 is not transmitted to rotation of the propeller 45. When the actuator 265 is slowly moved back downwardly, the serrations 263 and grooves 264 re-engage, so that the shaft 17 again drives the propeller 45.

Instead of a clutch 261, or in addition to it, a brake may be provided. The brake may be of any conventional construction capable of significantly slowing (or stopping) the rotation of the shaft 260.

If desirable, where the flexible shaft 260 makes its primary bend—as shown schematically at 270 in FIG. 38—low friction bearing material blocks or elements 271 may be provided to insure smooth rotation or the shaft 260, like the bearing eleven illustrated in U.S. Pat. No. 4,832,571. The bearing elements 271 may be supported by any suitable cross pieces 272 extending between the hulls 11, 12. Another conventional bearing 273, supported by cross piece 274, may also be provided adjacent the propeller 45 to further insure proper rotation of the shaft 260 to drive the propeller 45.

It is desirable to mount the flexible shaft 260—as seen in FIG. 38—so that during normal loading of the craft 10, roughly half of the propeller 45 is in the water, and half out. This propeller positioning may also be used with conventional shafts, that is not just with the flexible shaft 260.

In order to allow the craft 10 to move through the water most smoothly, at least the portions of the hulls 11, 12 normally engaging the water should be made of, or coated with, a low friction material. For example, the hulls may be made of fiberglass with a smooth gel-coat, or most desirably made of marine-grade polyethylene (Roplene®). Roplene is naturally buoyant, has about five times the impact resistance of fiberglass, has about the same weight as fiberglass, and does not need gel-coats or paint to be maintained or have very low friction (e.g. a coefficient of friction of about 0.003004).

The cross-sectional shape of the hulls 11, 12 that typically are in contact with water also affects the ease of movement of the craft 10 through the water. For example, an eighteen foot commercially available Hobiecat® catamaran may have a better shape for use with the invention than does the sixteen foot one. The optimum configuration—as illustrated schematically for the hull 11 in FIG. 41—is generally football-shaped (half a football) in cross-section. FIG. 41 is a front end view of the hull 11.

FIGS. 42-44 show another embodiment of a vertically collapsible wind turbine according to the invention. This is a bottom-supported embodiment of a vertically collapsible wind turbine. The vanes, spokes, and vane supports (as hereinafter described) may have the same materials, keying, and general configurations as described above with respect to the FIG. 35 embodiment.

In FIG. 42, the only vane collapsible vane support that is affixed to the shaft 17 (the bottom vane support also may be affixed to the shaft, but is not “collapsible) when the vertical axis wind turbine 215A is deployed in operating position is the second from the bottom vane support 276. The secured vane support 276 may be secured to the shaft 17, for example, by a threaded fastener 277, passing through cooperating openings 278, 279 in the vane support 276 and shaft 17. Any other conventional type of fastener may be used, however, and more than one fastener may be employed.

The vane support 276 may have any number of spokes 280 (e.g. two-six), with vanes 281 supported thereby, of any suitable configuration (e.g. Savonius). In the embodiment shown, the support 276 actually has spokes 280 that cooperate with vanes for both the lowest vane support (shown at 282 in FIG. 43), the third from bottom vane support 283 (see the vane 281A which is supported by spokes 280 from both the vane supports 276 and 283). The vanes 281 supported by the vane support 276 and the lowest vane support 282 (see FIG. 43) are offset with the vanes 281A supported by the vane supports 276, 283.

The upper vane supports 283, 284 (and perhaps others, as many as desired) are releasably secured to the vane support 276 for movement therewith. In the embodiment illustrated, this is accomplished by using a plurality of vertical supports 286 extending between the vane supports 276, 283, a plurality of vertical supports 287 extending between the vane supports 283, 284, a plurality of vertical supports 288 extending between the vane support 284 and the one above it (not shown), etc. Each of the vertical supports 286-288 is connected to two vane supports by fasteners, such as the conventional quick release fasteners 290 (e.g. like the fasteners 231).

The various vertical supports 286-288 are preferably angularly offset from each other around the circumference of the shaft 17, just like the vanes 281, 281A, 281B, and 281C are (see FIG. 44, which best shows this offset fir the vertical supports 286, 287 and the vanes 281A, 281B).

To collapse the vertical axis wind turbine 215A, the fastener(s) 277 is (are) removed, as seen in FIG. 43, which causes the vanes 281 to collapse, as the vane support 276 moves toward (and perhaps even in contact with, depending upon the volume of stiffness of the material of the vanes 281) the bottom vane support 282 (which is affixed to the shaft 17, and above the bearing 18). Then the vertical supports 286 are removed by detaching the fasteners 290 associated therewith, so that the vanes 281A collapse. This is also visible in FIG. 43, with the support 283 moving toward (and perhaps even contacting) the support 276. This process may be repeated for the vertical supports 287, 288 (and any others), in order, as desired.

To deploy the wind turbine 215A from a collapsed position (e.g. from the position of FIG. 43) the vane support 283 is moved to a position vertically spaced from the vane support 276 the same distance as the holes 292, 293 (see FIG. 43) in the vertical supports 286, which holes 292, 293 (and aligned holes—not shown—in the shaft 17) receive the fasteners 290. The fasteners 290 are then put in place (see FIG. 42). Then the vane supports 276, 282 are moved apart until the openings 278, 279 align, and then the fastener(s) 277 is (are) secured in place (see FIG. 42).

The holes 292, 293 in the vertical supports 286, 287, 288 etc. for receiving the fasteners 290 are vertically spaced the proper distance to vertically tension the vanes 281A, 281B, 281C, etc. If desired, a number of vertically spaced holes 294 may be provided to allow adjustment of the vertical tension in the vanes 281A, etc., for different wind conditions, or to accommodate stretching of the material of the vanes 281A, etc., during use over time.

FIGS. 45 & 46 schematically show a linkage embodiment of a collapsible wind turbine according to the invention. The nature of the collapse in the FIGS. 45, 46 embodiment is not property described as vertical, or as umbrella-like, although it includes aspects of each.

FIGS. 45 & 46 show the lowest (or perhaps second lowest), main, vane support 296 having at least one, and preferably two or more sets of, openings 297 which are dimensioned and positioned to receive spring pressed pins 298 or 299 which are connected to the wind turbine shaft 17 of a vertical axis wind turbine 215B. In solid line, FIG. 45 shows the wind turbine 215B deployed in operating position, while in dotted line FIG. 45 shows the wind turbine 215B in a collapsed, inoperable, position. In the operating position, the holes 296, 297 receive the pins 298, while in the collapsed position the holes 296, 297 receive the pins 299.

The main vane support 296 has two or more curved spokes 300 (two shown in FIGS. 45 & 46) extending radially outwardly therefrom. The spokes 300 are pivoted, such as by pivot pins 301, for rotation about a substantially horizontal axis. If desired, a stop—seen schematically at 302 in FIG. 46—may be provided to prevent pivotal movement significantly above the solid line position illustrated in FIG. 45.

The curved spokes 300 cooperate with other elements (hereafter described) to support vanes 303, which are preferably like the vanes 240, 281-281C, except that each vane 303 is releasably connected to a spoke 300. While any suitable quick connect and disconnect coupling may be provided, FIG. 45 illustrates a plurality of tabs 304 at the bottom edge 305 of the vane 303 each having a male snap 306. The male snaps 306 are adapted to cooperate with female snaps 307 placed on the outer surface (preferably at or near the top surface) of the spokes 300. When the tabs 304 are looped around the spokes 303, the snaps 306 thereof may be moved into operative engagement with the snaps 307, and thereby hold the vanes 300 taut in an operable position.

The spokes 300 cooperate with upper spokes 309 and substantially vertical links 310. The upper spokes 309 preferably have substantially the same curvature as the spokes 300, and are releasably or permanently (e.g. by looping and stitching) attached to the vanes 303. The spokes 309 are pivoted—such as by pivot pins 311—to the shaft 17, above the vane support 296, for pivotal movement about a substantially horizontal axis. The links 310 are pivoted substantially at the ends thereof to the spokes 300, 309 at or near the ends thereof, such as by pivot pins 312, 313, for pivotal movement about substantially horizontal axes.

To collapse the vanes 303, one unsnaps all of the snaps 306, 307 of the vanes 303, then one simply depresses all of the pins 298 at the same time to move them out of locking engagement with the holes 297. Then the vane support 296 is manually moved upwardly to the dotted line position of FIG. 45, wherein the holes 297 are aligned with the pins 299, and the pins 299 spring into the openings 297 to lock the support 296 in the dotted line position. The top of the support 296 acts as a cam on the pins 299 to depress them until they are aligned with the holes 297, and one or both of the top of the support 296 and the pins 299 may be angled or chamfered to facilitate the camming function. The spokes 300, 309 and links 310 approximately assume the position illustrated in dotted line in FIG. 45 when the support 296 is in the dotted line position, and the vanes 303 flap loosely. Alternatively, female snaps may be provided on the spokes 309, links 310, and/or the shaft 17 for cooperation with the male snaps 306 to hold the vanes 303 in an inoperable position. Alternatively, the vanes 303 may simply be manually wrapped around the spokes 309.

There may be other sets of vanes—e.g. see the vane 315 in FIG. 45—that are collapsed at the same time as the vanes 303 are collapsed. This may be accomplished by connecting the main vane support 296 to one or more other vane supports 316 using vertical supports 317. Each of the other vane supports 316 has two or more curved spokes 300 associated therewith, which cooperate with upper spokes 309 and vertical links 310, just as with the main vane support 296. The vanes 315 may also have tabs 304, and snaps 306 for cooperating with snaps 307 just like for the vanes 303. When the main vane support 296 is moved up into the inoperable position, or down into the operable position, the vane supports 316 move with it since they are operatively connected thereto by vertical supports 317.

While the movable linkage system of FIGS. 45 & 46 is preferred for some systems, it is also possible to have all of the spokes/links 300, 309, 310 substantially rigid, and move the vanes 303, 315 into inoperative position simply by unsnapping them (detaching snaps 306, 307), and into the operative position merely by snapping them (connecting snaps 306, 307). This is referred to as the readily detachable vane embodiment. In this embodiment, the spokes 309 are preferably attached to vane supports (as in the FIG. 35 or 42 embodiments) rather than to the shaft 17, and the vertical links 310 are optional.

A wide variety of fastening mechanisms may be provided instead of the snaps 306, 307, for both the linkage and releasable vane embodiments. Virtually any readily releasable conventional fastener system (e.g. eyelets receiving rotating tabs) may be utilized. One particularly desirable system is schematically illustrated in FIG. 46 for a vane 303. Cooperating hook and loop strips 319, 320, respectively (e.g. VELCRO®) are provided on the inside surface of the vane 303 adjacent the bottom 305 thereof. The strips 319, 320 are affixed to vane 303, and spaced apart and dimensioned and positioned so that when the bottom 305 is looped over the spoke 300 the hooks and loops come into contact with each other. The strips 319, 320 are wide enough to allow some adjustment of the tautness of the vane 303, e.g. to accommodate stretching when the vane 303 is of fabric that might lose some dimensional stability over time.

If vertical links 310 are provided, it may also be desirable to use hook and loop strips 321, 322, respectively, adjacent the side edge 323 of the vane 303. The side edge 323 is looped around the vertical link 310 so that the hooks and loops of the strips 321, 322 come into cooperating engagement. Again, the strips 321, 322 may be wide enough to accommodate some loss of dimensional stability of the material of vane 303 yet provide tautness of the vane 303.

Also, It will be seen from the above description that the invention also relates to several novel methods. That is the invention also includes: (A) A method of retrofitting an existing commercial catamaran (10) having a front cross-bar (13) from a sail boat to a turbine powered boat, comprising connecting a vertical axis wind turbine shaft supporting tube (25) to the front crossbar, inserting a shaft (17) of a vertical axis wind turbine (15) into the tube, removably mounting a propulsion system (see FIGS. 4 and 13) to the catamaran, and operatively connecting the shaft of the wind turbine to the propulsion system. This method also further comprises removing the wind turbine and propulsion system, and reconnecting a sail mast to the front crossbar. (B) A method of powering a land based powered mechanism at a dock using a watercraft having a vertical axis wind turbine (15) operatively connected to a propulsion system (e.g. see FIGS. 4 and 13), comprising: disconnecting the propulsion system from the wind turbine at a dock connecting the wind turbine to a land based powered mechanism, such as a pump or generator; and reconnecting the propulsion system to the wind turbine to move the watercraft in water.

While exemplary embodiments of the invention have been illustrated and described, it is to be understood that they are non-limiting, and other alternatives may be used. For example (and example only), the drive components for the fishtail 86 in FIGS. 13-20 may be more complex. For example, the fishtail 86 may be mounted on a generally vertical shaft extending through a bearing supported by the watercraft 10, with a pinion on top of the shaft. The crank arm 71 is pivotally connected to a lever at one end thereof, the other end of the lever pivotally connected to a rack that is mounted by the craft 10 for sliding movement from bow to stern. The rack cooperates with the pinion to move the fishtail 86 attached to the generally vertical shaft, preferably oscillating about 10-50 degrees. Still further, the very complex oscillating mechanism illustrated in U.S. Pat. No. 4,969,846 may be utilized, or the mechanism #894 of “1800 Mechanical Movements And Devices”, ©1911, 2000, Algrove Publishing Limited, may be utilized.

In the description all numerical values are approximate, and all narrow ranges within a broad range are specifically disclosed herein (e.g. a durometer of 40-100 includes 41-55, 61-91, 89-93, and all other narrow ranges within that broad range). The invention is to be accorded the broadest interpretation of the appended claims to encompass all equivalent devices and methods, and the broadest interpretation allowable considering the prior art. 

What is claimed is:
 1. A Savonius vertical axis wind turbine rotor comprising: a shaft, substantially vertical in use; a plurality of vane support hubs each having a plurality of at least partially curved spokes extending substantially radially outwardly therefrom; said vane support hubs operatively connected directly to said shaft and spaced vertically from each other along said shaft to provide a plurality of sets of vertically spaced spokes; and a plurality of vanes, one for each set of spokes operatively connected to said at least partially curved spokes to provide surface area for engaging wind.
 2. A Savonius wind turbine rotor as recited in claim 1 wherein each vane support hub has exactly three spokes.
 3. A Savonius wind turbine rotor as recited in claim 1 wherein said vane support hubs are operatively connected to said shaft using mechanical fasteners.
 4. A Savonius wind turbine rotor as recited in claim 3 wherein said vanes are connected to said spokes using mechanical fasteners.
 5. A Savonius wind turbine rotor as recited in claim 3 wherein said mechanical fasteners are removable.
 6. A Savonius wind turbine rotor as recited in claim 3 wherein said mechanical fasteners directly connect said vane support hubs to said shaft.
 7. A Savonius wind turbine rotor as recited in claim 1 wherein said rotor is devoid of structural end caps.
 8. A Savonius wind turbine rotor as recited in claim 1 wherein at least four vane support hubs are provided vertically spaced along said shaft, with the spoke sets thereof substantially vertically aligned with each other.
 9. A Savonius wind turbine rotor as recited in claim 1 wherein said vane support hubs and spokes are integral and made of metal or fiber reinforced plastic.
 10. A Savonius wind turbine rotor as recited in claim 9 wherein said vanes are made of sheet metal.
 11. A Savonius wind turbine rotor as recited in claim 9 wherein exactly three spokes are provided for each vane support hub, and wherein at least four vane support hubs are provided vertically spaced along shaft, with the spoke sets thereof substantially vertically aligned with each other.
 12. A Savonius wind turbine rotor as recited in claim 11 wherein said rotor is devoid of structural end caps.
 13. A Savonius wind turbine rotor as recited in claim 12 wherein said vanes are connected to said spokes using mechanical fasteners.
 14. A Savonius wind turbine rotor as recited in claim 13 wherein said vane support hubs are operatively connected to said shaft using mechanical fasteners.
 15. A Savonius wind turbine rotor as recited in claim 1 in combination with at least one bearing assembly mounting said shaft substantially vertically for rotation about a substantially vertical axis, and a propeller, electricity generating device, or pump operatively connected to said shaft to be powered thereby.
 16. A vane support assembly for a Savonius or open helix vertical axis wind turbine comprising: a vane support hub defining a through-extending opening therein; a plurality of at least partially curved spokes integral with said vane support hub and extending substantially radially outwardly therefrom; and an adaptation part of said hub which allows said hub to be operatively connected to a substantially vertical shaft extending through said through-extending opening, for rotation with the shaft.
 17. A vane support assembly as recited in claim 16 wherein said vane support hub includes exactly three integral spokes, and wherein said vane support hub and integral spokes are of metal or fiber reinforced plastic.
 18. A vane support assembly as recited in claim 16 wherein said adaptation part includes an opening for receiving a mechanical fastener.
 19. A Savonius or open helix vertical axis wind turbine comprising: at least one bearing; a substantially vertical shaft mounted by said at least one bearing for rotation about a substantially vertical axis; at least four vane support hubs each having a plurality of at least partially curved spokes extending substantially radially outwardly therefrom; said vane support hubs operatively connected to said shaft and spaced vertically from each other along said shaft to provide a plurality of sets of vertically spaced spokes; a plurality of vanes, one for each set of spokes operatively connected to said at least partially curved spokes to provide surface area for engaging wind; wherein said turbine is devoid of structural end caps; and a propeller, electricity generating device, or pump operatively connected to said shaft to be powered thereby.
 20. A vertical axis wind turbine as recited in claim 19 wherein exactly three spokes are provided for each vane support hub, and wherein said spokes and hub are integral; and wherein said hubs are operatively directly connected to said shaft. 